The predicable demand for data, and corresponding increase in data delivery capacity, has come to be known as Cooper's Law (which states that the total capacity will double about every 30 months). In order to meet the rapidly growing demand for mobile data, one strategy may be to use smaller cells. The use of small cells may imply an increased spatial reuse of the same spectrum to achieve greater capacity.
The use of additional spectrum, for example 3.5 GHz and higher frequencies, may be used to get large bandwidth channels. In order to close the link budget for millimeter wavelengths (mmWs), highly directional antennas may be needed. The use of higher frequencies and directional antennas may make it less likely that a transmission may cause much interference for unintended receivers. The use of high frequency carriers (e.g., in the mmW spectrum) may make wide amounts of spectrum available. As an example, for 60 GHz, the available unlicensed spectrum may be 7 GHz wide. Additional unlicensed spectrum may be available as licensed, lightly licensed, or unlicensed spectrum.
A mmW Hotspot (mmH) architecture may be driven by the need for small cells and the use of mmW carrier frequencies. The mmH architecture may include small mmW base stations overlaid on a cellular network. The mmW base stations may be denser than the traditional macro eNBs. The mmW base stations may use mmW MESH networks as backhaul to the macro eNBs (or other wired/wireless aggregation points). Phased array antennas may be used to provide backhaul links. Limited available transmit (TX) power and a low interference environment of phased array antennas may enable a flexible backhaul architecture. The phased array antennas may create narrow steerable beams. The narrow steerable beams may provide backhaul links that may be easier to deploy than adding new wired backhaul links. Because the beams are narrow and steerable, the beams may provide an adaptable MESH backhaul with pseudo-wired low interference connections between backhaul links.
The coexistence of a macro cell layer and a small (e.g., mmW) cell layer may lead to user equipment (UE) connected to both the macro and the small-cell layer simultaneously. Dual-connectivity may introduce new challenges for battery consumption of the UE. For a UE that may be connected to a small cell layer and a macro cell layer, current discontinuous reception (DRX) mechanisms may be inadequate.